Sound cleaner?

Hi, I'm looking for a freeware tool that can smooth and clean sound files that are saved with a low sampling rate. I got some 8 kHz Samples and I'd like them with a bit better quality. I know, some of the loss can hardly be undone, but I guess with some half-intelligent interpolation it may be at least a bit better in the end. Any ideas?

uh, do you got the wav code somewhere? When I got the sample in a bank then it's easy, of course and also fun. But until then it's a lot of searching etc. and this is sometimes a matter of a good google-karma. Which I don't have these days.

Besides - I am sure someone else did it already,so why should I reinvent the wheel? especially since I'm not a specialist.

Sometimes it's worth to search for existing solutions because they ore usually better thatn what you can do in one hour.

Not so long ago I started a greenscreening App for Videos because my Video Editor from MAGIX has bad greenscreening support. I spent a lot of hours to realize that it isn't that easy. Now I have found "Zwei-Stein", a freeware video editor that has nice greenscreening built in.

Well at least I still can utilize the code for reading and saving Avis for special fx apps, that's where the power of Blitz3D comes in anyway.

As far as I know, fixing low quality samples isn't easy. An 8khz sample doesn't actually have any of the higher frequencies, so you can't exactly recover them.

I looked for such a program a while back because I bought a sound CD with lots of poor quality samples, but I never found anything better than what I could do manually with sound forge, and I wasn't exactly doing a great job on them.

The best you can probably do is convert the sample to 44khz and 16 bit, and then try to use the equalizer on it. You'll be trying to get back some of the higher frequency sounds so the sample doesn't sound like it has so much bass. I don't think you'll ever get anything approaching a clean sounding sample with good frequency range though. At least, not with my level of sound editing expertise or less. I don't know what an expert sound designer could do with such a sound, but I suspect they wouldn't even bother with it and would just buy a better sound or make their own.

Btw, there was a sound cleaning plugin I had for sounf forge at one time. It was intended for removing noise in a sample. The idea was you would select a blank section of your recorded sound, which had static, and it would remove those frequencies from the main recording, thus canceling out noise. But this only really worked if you had a sample which had blank space so you could build the noise profile. And if I remember correctly it didn't really do anything for low bitrate sample "noise".

Good info there Swift. Fixing Low Quality samples is not easy at all. Music technology eh, :)My intention was to play with the samples inside the WAV.. Blitz seems to bring in artifacts in low samplerate sounds, so upping them to 44.1khz and interpolating yourself will likely fix this issue. The source code to this is what i was going to release.....

Converting from 8kHz to 44.1kHz in goldwave won't do the trick. a simple interpolation is nice. Using bezier curves even better. There may be even better practices. EG. when you assume that the file was converted from 44.1 kHz to 8kHz, you can use this to predict missing information, using a reverse moire pattern resolver (or something).